Re: [RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-23 Thread Mark Rutland
On Mon, Mar 15, 2021 at 11:57:54AM -0500, madve...@linux.microsoft.com wrote: > From: "Madhavan T. Venkataraman" > > Apart from the task pt_regs, pt_regs is also created on the stack for other > other cases: > > - EL1 exception. A pt_regs is created on the stack to save register >

Re: [RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-19 Thread Madhavan T. Venkataraman
On 3/19/21 11:20 AM, Mark Brown wrote: > On Fri, Mar 19, 2021 at 10:02:52AM -0500, Madhavan T. Venkataraman wrote: >> On 3/19/21 9:40 AM, Madhavan T. Venkataraman wrote: > >>> Actually now I look again it's just not adding anything on EL2 entries >>> at all, they use a separate set of macros

Re: [RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-19 Thread Mark Brown
On Fri, Mar 19, 2021 at 10:02:52AM -0500, Madhavan T. Venkataraman wrote: > On 3/19/21 9:40 AM, Madhavan T. Venkataraman wrote: > > Actually now I look again it's just not adding anything on EL2 entries > > at all, they use a separate set of macros which aren't updated - this > > will only update

Re: [RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-19 Thread Madhavan T. Venkataraman
On 3/19/21 9:40 AM, Madhavan T. Venkataraman wrote: >> Are you referring to ARMv8.1 VHE extension where the kernel can run >> at EL2? Could you elaborate? I thought that EL2 was basically for >> Hypervisors. > KVM is the main case, yes - IIRC otherwise it's mainly error handlers > but I might

Re: [RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-19 Thread Madhavan T. Venkataraman
On 3/19/21 8:22 AM, Mark Brown wrote: > On Thu, Mar 18, 2021 at 05:22:49PM -0500, Madhavan T. Venkataraman wrote: >> On 3/18/21 12:40 PM, Mark Brown wrote: > >>> Unless I'm misreading what's going on here this is more trying to set a >>> type for the stack as a whole than for a specific stack

Re: [RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-19 Thread Mark Brown
On Thu, Mar 18, 2021 at 05:22:49PM -0500, Madhavan T. Venkataraman wrote: > On 3/18/21 12:40 PM, Mark Brown wrote: > > Unless I'm misreading what's going on here this is more trying to set a > > type for the stack as a whole than for a specific stack frame. I'm also > > finding this a bit

Re: [RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-18 Thread Madhavan T. Venkataraman
On 3/18/21 12:40 PM, Mark Brown wrote: > On Mon, Mar 15, 2021 at 11:57:54AM -0500, madve...@linux.microsoft.com wrote: > >> To summarize, pt_regs->stackframe is used (or will be used) as a marker >> frame in stack traces. To enable the unwinder to detect these frames, tag >> each

Re: [RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-18 Thread Mark Brown
On Mon, Mar 15, 2021 at 11:57:54AM -0500, madve...@linux.microsoft.com wrote: > To summarize, pt_regs->stackframe is used (or will be used) as a marker > frame in stack traces. To enable the unwinder to detect these frames, tag > each pt_regs->stackframe with a type. To record the type, use the

[RFC PATCH v2 2/8] arm64: Implement frame types

2021-03-15 Thread madvenka
From: "Madhavan T. Venkataraman" Apart from the task pt_regs, pt_regs is also created on the stack for other other cases: - EL1 exception. A pt_regs is created on the stack to save register state. In addition, pt_regs->stackframe is set up for the interrupted kernel